Heat 1 tablespoon of the oil in a 25cm non-stick frying pan with a flameproof handle. Add the onion and cook for 2–3 minutes or until starting to soften. Stir in the garlic, cumin, ground coriander and cayenne pepper and continue cooking for 1 minute, stirring constantly.
Add the remaining 1 tablespoon of oil to the pan, then add the potatoes, red capsicum and eggplant. Continue sautéing for 5 minutes, stirring frequently, until the vegetables are lightly browned.
Add the water, cover and steam for 5 minutes. Then remove the lid and continue cooking until all excess liquid has evaporated. Stir in the chickpeas.
Lightly beat the eggs in a large mixing bowl. Add the chopped coriander and season with pepper to taste. Add the vegetable and chickpea mixture from the pan and stir to mix.
Preheat the grill to high. Coat the frying pan with cooking spray and heat over a medium heat. Pour in the egg mixture, spreading out the vegetables evenly. Cook the omelette, shaking the pan from time to time, for 3–4 minutes or until almost set; there will still be some uncooked egg mixture on the top.
Place the pan under the grill and cook the omelette for 2 minutes or until the top looks set. Remove from the heat and allow the omelette to rest in the pan for 2 minutes, then slide it on to a serving plate or board. Serve hot, cut into wedges.